简介:在对热电致冷器的驱动原理和特点进行分析的基础上,提出了一种适用于非致冷红外焦平面热成像探测器的高精度微型化PWM温度控制器的设计方案,并对其电路原理与设计进行了详细论述.该设计也适合于在光纤通信用激光模块、光放大器、微型精密黑体以及高性能晶体振荡器等方面的应用.
简介:Asimplifiedringcavityforachievingaunidirectionalroomtemperaturemulti-wavelengtherbium-dopedfiberringlaserwithoutopticalisolatorisdemonstrated.ThefiberringcavityisbuiltinsuchawaythattheopticalfieldspropagatingintwodirectionssufferdifferentlossescausedbyonesampledfiberBragggrating.Furthermore,simultaneousmulti-wavelengthlasingwith0.8-nmintervalsisdemonstratedwithsinusoidalphasemodulationjustbeforethesampledfiberBragggratingtopreventsingle-wavelengthlasingandunstablewavelengthoscillation.
简介:Amaster-slaveconfigurationusedtocontrolthenonlinearbehaviorsarisinginaverticalcavitysurfaceemittinglaser(VCSEL)withstrongexternalopticalfeedbackisestablished.Intermsofbifurcationdiagram,timeandfrequencydomain,theinfluenceofthecontinuousopticalinjectionfromthemasterVCSELonthenonlinearcharacteristicsoftheslaveisinvestigatedtheoretically.Forrelativelyweakinjection,theslavestillkeepsitsintrinsicnonlinearstate.Withincreasingtheinjectionstrength,thesenonlinearbehaviorsevolvetoperiodicfluctuation,andatlastarereplacedbythesteady-state(e.g.thecriticalinjectionparameterforsteady-stateis1.2whenexternalcavity'sreflectivityandlengthare4%and4cm,respectively).Duringthisevolutionthebifurcation-contractionphenomenaarealsoobserved.
简介:Byusingasphericalwaveasthereferencewave,werecordedthein-linephase-shiftingdigitalhologramofthe25thelementofChinesestandardNo.3resolutiontestpattern,andgavethecorrespondingnumericalreconstructedresults.Someproblemsconcerningwiththedigitalhologramrecordingandreconstructionofthediffractiveobjectatashortdistancearediscussed.Theexperimentalresultshowsthattheresolutionofthereconstructedimageisbetterthan10μm,whichisthelimitbyusingthisexperimentalarrangement.
简介:Anexperimentofadaptivepolarizationmodedispersion(PMD)compensationfor40-Gb/sreturn-to-zero(RZ)opticalcommunicationsystemisreported.Intheexperiment,degreeofpolarization(DOP)isusedasfeedbacksignalandparticleswarmoptimization(PSO)methodisadoptedaslogiccontrolalgorithm.Thecompensationtimeisabout200ms,thecompensateddifferentialgroupdelay(DGD)isupto30ps,andbiterrorrate(BER)of10^-9isreachedwhenPMDcompensationisemployed.
简介:Atemperaturesensorbasedonpolarizationnon-reciprocity(PNR)infiber-opticSagnacinterferometer(FSI)wasproposed.Theexperimentalstudywasmadeprimarilyandtheresultsagreewiththeorywell.Discussionshowsthatthiskindoftemperaturesensorcanachievehighprecisionandhavegreatapplicationpotential.